Bending and anvil die for fmgmt



July 19, 1949. B. GREE N i 2,476,596

BENDING AND ANVIL DIE FOR TANGENT BENDING APPARATUS Filed D601. 28, 1946 3 Sheets-Sheet l JNVENTOR. 5 4 [6 5 Gaza/v w, Mi;

. 1.. B. GREEN 2,475,596

BENDING AND ANVIL'DIE FOR TANGENT BENDING APPARATUS July 19, 1949.

3 Sheets-Sheet 2 Filed Dec. 28, 1946 HIIHHHHHHWrfie 6 INVENTQR. 7 LEE 5.62M

flrrae/vsys L. B. GREEN July 19, 1949.

I BENDING AND ANVIL DIE FOR TANGENT BENDING APPARATUS 3 SheetsSheet 5 Filed Dec.

INVENTOR. 56 5, GfiEE Patented July 19, 1949 UNITED STATES PATENT OFFICE BENDINGAANDV ANVIL DIE roe TANGENT BENDING APPARATUS Lee B. Green, Lakewood,- Ohio Application December 28, 1946; serial filo. new

4 Claims. 1

This invention relates to bending machines of the kind intendedfor use in bending flanged metal workpieces. More specifically, the invention relates to apparatus for bending workpieces of the type having a web portion and one or more continuous longitudinal flanges and with which the workpiece is bent to a curved or angular shape by bending the web portion out of its @Lvn plane and simultaneously bending the flange or flanges within their own planes.

The invention provides an improved bending machine or apparatus of this character in which novel means is employed for minimizingthe tendency of the flange portions of the workpiece to wrinkle or buckle during the bending o era tion and for subsequently smoothing or ironing out such wrinkles or bulges as may actually occur in the flange portions of the workpiece.

Another object of the present invention is to provide bending apparatus of the character men tioned, having cooperating die members for ac= complishing the bending operation and in which one of the die members has retaining" and ironing means thereon adapted to cooperate with flange portions of the workpiece for decreasing the tendency to buckle and for subsequently smoothing out such wrinkles as may actually occur.

A further object is to provide improved bend ing apparatus of the kind embodying a group of cooperating die members including a pair or die members having a partingjline therebetween and also having side flanges adapted to engage edge flanges of the workpiece and wherein the side flanges of one of the die members of the pair has extension portions adapted to span the parting line and to exert holding. and smoothing actions on the flanges of the workpiece;

Still another object is to provide improved bending apparatus of the character mentioned, in which one-of the die members is an anvil die and another isa bending die which is rockable around the anvil die for bending. the flanged workpiece therearound and wherein the side flanges of the bending die have extension portions which exert a holding action on the flange portions of the workpiece during the working travel of the bending die and have a smoothing or ironing action on the flange portions during the return travel of the bending die..

The invention can be further briefly summarized as consisting certain novel combinations and arrangements of. parts" hereinafter described and particularly? set out in" the claims hereof.

In the accompanying sheets" of drawings Fig.1 is a side elevation at a bending machine embodying the present invention;

Fig. 2 is apartialtop planview Of the machine;

Fig;- 3 is a longitudinal sectional elevation taken through the machine substantially as indicated by line 3:3 of Fig. 2;;

Fig. 4- is a partial longitudinal sectional eleva tion similar to Fig. 3 but showing the position of the bendingv die at or near the end of its Working travel;

Fig. 5 is a partial vertical sectional view taken near the front end of the machine as indicated by line 5-5 of- Fig.- 3";

Fig. 6 is a; partial: vertical sectional view taken on line 6 5 of Fist 5 and showing the fulcrum mounting for the rocker plate Figs. 7 and 8 are perspective views showing a pair of the cooperatingdie members in detached relation, and;

Fig. 9 is a perspective view showing a workpiece after the bending operation thereon but prior to the smoothing or ironing operation on the edge flanges thereof.

As one embodiment-of the present invention the accompanying drawings show a bending machine or apparatus H] for carrying out a bending operation on a flanged or channel-shaped metal workpiece such asthe workpiece ll shown in this instance. A bending machine of the type here shown. is more fully disclosed in earlier application; Serial-Bio; 571-979} flled January 9', 1945.

The machine it! includes a frame having laterally spaced upright side walls t2 and an upright front wall l'3 extending between suchside walls and having thereon a die support or bolster l4 whichalso extends laterally betweenthe side walls [2 and carries a die member l5. The machine also includes a pivoted carrier [6 which islocated between the side walls 12 and carries a second die member IT The carrier Hi comprises a pair of rearwardly extending arms tiialocated' adjacent the side waiis I2 and having their rear ends pivoted on such-sidewalls by means or the pivot pins is; At its forward end the carrier is is provided with a transverse beamis on which the die" member II is inoui ted as by means of the T slots 2n and b oit's 21'. The machine le also includes a wing 23" extending across the front or the machine and' whicn is pivoted on the frame for forward and i pwar i swinging" movement around the die" inefnber' l'l'. The wing 23' carries a rockerpl ate 24 on which a third die" member 25 is fiidllfifid; v V

The 'irn: E3 is here shown as being honow metal structure having a" pair of arms 21- which are pivoted on pivot pins 28 carried by the sides l2 of the frame. The wing contains a pressure roller 29 which acts on the flat undersurface of the rocker plate 24 and is urged thereagainst by compression springs 39. The rocker plate 5 is fulcrumed on the frame of the machine for the desired rocking movement around the die member I1 and for this purpose the sides ii of the frame are provided with gear sectors 31 which are suitably mounted thereon in substantially concentric relation to the pivot pins 28. The rocker plate 24 has racks 32 mounted thereon adjacent its opposite side edges and which mesh with the gear sectors 3|, as shown in Fig. 6.

Swinging of the wing 23 forwardly and upwardly causes a working stroke of the bending die member 25, as is explained morefully hereinafter, and swinging of the wing downwardly and rearwardly returns this die member to its initial position in which it is illustrated in Fig. 3. Suitable power means is employed'for imparting these swinging movements to the wing 23, such as the pair of inclined hydraulic'cylinders 3 3 shown in this instance and which are located adjacent the side walls [2 of the frame and have their lower rear ends pivotally connected with the frame by means of the brackets and pivot pins 36. The cylinders 34 have piston rods 3? projecting therefrom and operably connected with the wing 23 by the pivot pins 38.

Suitable actuating means is also provided for the carrier i6 for producing a desired actuation of the die member ll. This actuating means is here shown as comprising an upright hydraulic cylinder to located between the side walls i2 and having its lower end pivotally mounted on the frame by means of the pivot pin M A piston rod 62 projectin from the upper end of the cylinder 30 is connected with a rockshaft 43 by means of the lever 44. A pair of laterally spaced levers d5 are carried by the rockshaft 53 and are connected with the arms lfia of the carrier 16 by means of the links 46.

Oil under pressure, or other suitable motive fluid, is supplied to the power cylinders 34 and by a pump 43 which is driven by an electric motor 49 through the belt 59. A tank or reservoir 5i contains a suitable supply of such oil or motive fluid. v

The workpiece which is shown in this instance is an elongated sheet metal member having an intermediate'web portion Ila and continuous longitudinal edge flanges lib. The workpiece I i is initially in the form of a straight channel-shaped length, as shown in Fig. 3, and,during the bending operation performed thereon by the present apparatus the web portion Ila is bent out of its own plane to the curved shape shown in Fig. 9 and the edge flanges lib are simultaneously bent within their own planes.

During this bending operation there is a tendency for the edge flanges lib to become wrinkled or buckled at or adjacent the beginning of the curve being formed therein. The die members which will be presently described in greater detail exert a holding action on the flanges I'ib tending to prevent the formation of such wrinkles or bulges and also act to iron or smooth out any such wrinkles or bulges as may actually occur. For the purpose of better describing the invention, the workpiece H is shown in Fig. 9 as having wrinkles or bulges 53 in the edge flanges lib thereof but it will be understood of course that these wrinkles or bulges will not be present in the completed workpiece because they will have been ironed or smoothed out by the die members.

The die member l5 of the above mentioned die group is a work-supporting and clamping member. The die member I! is a work-clamping member and is actuated by the carrier it for cooperation with the die member l5 for clamping the workpiece ll therebetween. The die member ii is also an anvil member having a curved anvil portion l'la about which the workpiece l i is bent. As mentioned above, the member 25 is a bending die which is rockable about the anvil die member IT.

The die member [5 is best illustrated in Fig. 7 and comprises a plate or body having a substantially flat intermediate portion 54 upon which the web portion Ha of the workpiece ii is received and also having substantially parallel side flanges 55 on opposite sides of the flat portion 54. The die member i5 also has lateral projections or flanges 56 thereon enabling the same to be bolted or otherwise connected to the support or bolster id of the frame. The side flanges 55 overlappingly engage the outer side faces of the edge flanges iib of the workpiece. These side flanges are preferably formed in part by integral projections of the body of the die member I5 and in part by Wear strips 57 of an angular cross-sectional shape which are recessed into the body of this die member.

The die member ll has a width transversely of the machine it! such that it will snugly enter the channel recess of the workpiece H and has a substantially flat bottom face 59 for clamping engagement with the web portion I l a of the workpiece. This die member also has flat side faces Gil which are engaged by the inner faces of the edge flanges i lb of the workpiece and against which these flanges are held by the side flanges 55 of the die member 15. The anvil portion Ila of the die member H is located at the front thereof and has the desired shape or curvature to which the workpiece I l' is to be bent. This curved anvil surface usually conforms to an arc whose center of curvature lies on the axis about which the wing 23 is swung, that is to say, lies on the axis of the pivot pins 28.

The bending die member 25 is generally similar to the die member I5 and comprises a plate or body having a flat intermediate portion 62 and substantially parallel side flanges 63 located on opposite sides of such flat portion and spaced apart so as to lie in alignment with the side flanges 55 of the die member 15 when the bending die member is in its initial position as shown in Fig. 3. The bending die member 25 preferably has lateral flanges 64 thereon enablin the same to be bolted to the upper surface of the rocker plate 2 3 of the wing 23. The side flanges 63 of the bending die are preferably formed in part by integral portions of the body of this die memher and in part by wear strips 65 of an angular cross-section and which are recessed into the body of this die member as shown in Fig. 8.

Although the side flanges of the die members i5 and 25 have been described above as being preferably formed in part by integral portions of the die bodies and in part by the wear strips 5'! and 65, it should be understood that the wear strips could be omitted or, if desired, the side flanges could be formed by the wear strips alone.

When the wing 23 is in its lower position, as shown in Fig. 3, the bending die member 25 is in an initial position in which its flat surface 62 is horizontally aligned with the flat surface.

of the die member I and these two flat surfaces form a support upon which the web portion I'Ia of the workpiece rests when the workpiece is inserted into the machine. At this time the adjacent edges I51]. and 25a of, the die members i5 and 25 are substantially in meeting relation and define therebetween a common parting line 68 across which the workpiece extends. The side flanges 93 of the bending die member 25 also overlap the flat side faces 60 of the anvil die I1 and hold the edge flanges Ilb of the workpiece thereagainst. As shown in Fig. 3- the curved anvil portion Ila of the die member I! overhangs the parting line 66.

An important feature of the die mechanism of the improved bending apparatus is the means by which the tendency for the edge flanges MD to buckle or wrinkle is decreased and by which wrinkles or bulges 53 which may actually form in such edge flanges are smoothed or ironed out. lhis means Comprises extension. portions 68 formed onv the side flanges 63, or preferably on the wear strips 65, oi. the bending die member 25 and which portions or projections overhang the edge 25a so as to span. the parting line 66 when the bending die member is in its initial position. The side flanges 65- of. the die member I5, or preferably the wear strips 51 thereof, have recesses 69 extending into the ends thereof from the edge Ito. The projections 68 of the bending die member 25 are preferably of a tapered or rounded form and the recesses 69 of the die member I5 are oi a corresponding shape so that the projections will be snugly received therein.

To explain the operation of the improvedbending apparatus let it be assumed. that the bending die member 25 is in its initial position as shown in Fig. 3 and. that the workpiece II has been inserted, The cylinder M1- is then. actuated to cause the upper die member IT to clamp the workpiece against the lower die member I5. The cylinders 34 are then: actuated to swing the wing 23 forwardly and upwardly thereby causing the rocker plate 24 to rock on the gear sectors 3i 1 and also causing the bending die member 25 to rock around the curved anvil portion I'Ia of the die member Il. slippage of the bending die member 25 on the curved anvil portion is prevented during this rocking movement by the meshing of the racks 32 with the gear sectors 3!. The rocking of the bending die member 25 around the anvil portion II'a, bends the workpiece I I around the latter and. the working stroke or travel of the bending die member continues until this member reaches the position. shown in Fig. 4. During this bending operation the web portion IIa is bent out of its own plane and the edge flanges I ID are bent within their own planes.

The rocking movement of the bending die member 25 also causes the edge 25a, thereof to move away from the adjacent edge I5a of the die member I5 and since this leaves portions of the edge flanges I lb of the workpiece exposed at or adjacent the parting line 66, the wrinkles or bulges 5-3 may occur in the edge flanges at this point. As the edge 25a. of the bending die member 25 moves away from the adjacent edge I5a of the die member I5 the extension portions 68 of the side flanges of the bending die member are withdrawn from the recesses 69 of the die member I5, but since these extension portions overhang the edge 25a they will maintain the edge flanges I lb of the workpiece covered during a portion of such separating movement and will thus materially reduce the tendency for aria 59c Wrinkles or bulges to be formed in the edge flanges.

When the working stroke oi the bending die member 25 has been completed the cylinders 34 are actuated to swing the wing 23 back to its lowered position as shown in Fig. 3.. This downward swinging of the wing causes a return movement of the bending die member 25 to its initial position and during this return movement the projections 8-8 accomplish an ironing action on the wrinkles 53 and cause the latter to be smoothed back into the planes of the edge flanges lib. During this ironing action the projections 68 sweep over the wrinkles 53 by moving thereacross in a direction from the web portion Ila toward the free edges of the flanges III). This causes the wrinkles 53 to be flattened back into the planes of the edge flanges and during the accomplishment of this function the projections 68 re-engage in the recesses E9 of the die member 55 as the bending die member '25 assumes its initial position.

From the foregoing description and the accompanying drawings it will now be readily understood that the improved bending apparatus herein disclosed is adapted to accomplish a desired bending operation on a flanged or channelshaped workpiece and that the cooperating die members thereof tend to prevent wrinkling or buckling of the flange or flanges of the workpiece and also act to produce a smoothing or ironing action on the flange or flanges for smoothing out wrinkles or bulges which may have occurred therein during the bending operation. Since any wrinkles or bulges which may occur in the flange or flanges of the workpiece will thus be automatically smoothed out during the return movement of the bending die member it will be seen that finished. workpieces of a desired smooth and. uniform character will be produced and it will not be necessary to subject them to further machine or manual operations for working bulges or wrinkles out of the flange or flanges thereof.

Although the improved bending apparatus has been illustrated and described herein in some detail it will be understood of course that the invention is not to be regarded as being correspondingly limited but includes all changes and modifications coming within the scope of the claims hereof:

Having thus describedmy invention, I claim:

1. In bending apparatus of. the character described, a pair of die members having adjacent edges defining a parting line and each die member having a pair of substantially parallel side flanges thereon one die member of said pair being a holding die member and the other being a bending die member, and an anvil die member adapted to cooperate with said holding die member for holding therebetween a metal workpiece having a web portion and longitudinal edge flanges, said anvil die member having a curved anvil portion and said bending die member being rockable about said curved portion for bending the web portion of the workpiece out oi its own plane and around said anvil portion and simultaneously bending said edge flanges within their own planes, the side flanges of one die member of said pair having recesses extending thereinto from said parting line and the side flanges of the other die member of said pair having extension portions of a length to span said parting line and engage in said recesses.

2. In apparatus for bending a metal workpiece of the type having anintermediate web portion and longitudinal edge flanges, a die member having an intermediate plate portion and substantially parallel side flange portions, a second die member adapted to extend between said side flange portions for cooperation with the first die member in holding the web portion and edge flanges of said workpiece thereagainst and having a curved anvil portion, and a bending die member also having an intermediate plate portion and substantially parallel side flange portions and being rockable around said curved anvil portion for bending said web portion of the workpiece out of its own plane and around said anvil portion and simultaneously bending the edge flanges of the workpiece within their own planes, said bending die member having an initial position in which its side flange portions are substantially in alignment with the side flange portions of said first die member and in which adjacent edges of said first die member and bending die member are in substantially meeting engagement and define a parting line, said side flange portions of said first die member having recesses extending thereinto at one end thereof from said parting line and said side flange portions of said bending die member having end projections thereon of a length to span said parting line when said bending die member is in said initial position and adapted to move into and out of said recesses during rocking of said bending die member around said anvil portion.

3. In bending apparatus of the character described, an anvil die member engageable with one side of a metal workpiece having a web portion and a longitudinal edge flange, said anvil die member having a curved anvil portion and a substantially flat side face, a second die member engageable with the other side of said workpiece for clamping the same against said anvil die member and having a. side flange overlapping said flat side face for holding said edge flange of the workpiece thereagainst, means supporting said anvil die member and said second die meanber so that one of these die members is movable 1 relative to the other for clamping or releasing the workpiece, means for actuating said one die member, a bending die member rockable around said curved anvil portion for bending said web portion therearound and out of its own plane and 5 portions which define a common parting line when said bending die member is in its initial position and across which parting line said workpiece extends, the side flange of said second die member terminating short of said parting line and the side flange of said bending die member having an end extension of a length to span said parting line 'when said bending die member is in said initial position and which exerts an ironing action on said edge flange during rocking of said bending die member.

4. In a bending machine of the character described a frame, a pair of cooperating clamping die members adapted to receive therebetween a metal workpiece having a web portion and a continuous edge flange, one of said die members being movable for clamping the workpiece against the other die member and one of said die members having a curved anvil portion adapted for bending of said web portion there- 7 around and a substantially flat side face adapted to be overlappingly engaged by said edge flange, a bending die having an initial position in which it cooperates with one of said clamping die members in defining a parting line and being rockable in one direction about said anvil portion for bending said Web portion out of its own plane and around the latter and simultaneously bending said edge flange within its own plane, said bending die having a side flange overlapping said side face of the anvil die for holding said edge flange against the latter and said bending die being rockable in the other direction to return the same to said initial position, a carrier for said bending die, said carrier being mounted on said frame for swinging movement so as to cause said rocking of said bending die, and means for swinging said carrier, the side flange of said bending die having an extension portion of a length to span said parting line when the bending die is in said initial position and adapted to iron said edge flange against said side face during the return movement of the bending die.

LEE B. GREEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 839,839 Hallowell. Jan. 1, 1907 1,021,526 Huston Mar. 26, 1912 1,258,892 Grifl'in Mar. 12, 1918 2,190,423 Henricson Feb. 13, 1940 2,287,933 Green June 30, 1942 

